Yohimbine induces sympathetically mediated renin release in the conscious rat. Eur J Pharmacol 1984 Jan 27;97(3-4):247-55
Date
01/27/1984Pubmed ID
6323192DOI
10.1016/0014-2999(84)90456-4Scopus ID
2-s2.0-0021332374 (requires institutional sign-in at Scopus site) 9 CitationsAbstract
The preferential alpha 2-adrenergic antagonist yohimbine (4 mg/kg s.c.) caused a time-related increase in serum renin activity and heart rate in conscious Sprague-Dawley rats. Although mean arterial pressure was not decreased significantly over the 2-h period, heart rate was elevated significantly at 15 and 30 min post-injection. In contrast, serum renin activity remained elevated for up to 2 h with a 9-fold and 9.7-fold increase occurring at 30 and 60 min post-injection, respectively. Yohimbine (0.3, 1, 3 and 10 mg/kg s.c.) elicited a dose-related increase in serum renin activity and heart rate (30 min post-injection). The 1 mg/kg dose of yohimbine did not alter blood pressure whereas the 3 mg/kg dose caused a variable decrease in mean arterial pressure. The highest dose of yohimbine (10 mg/kg) significantly lowered blood pressure. The beta-adrenergic receptor antagonist propranolol (1.5 mg/kg s.c.), blocked the renin release and tachycardia caused by yohimbine (1 and 3 mg/kg s.c.), and the ganglionic blocking agent chlorisondamine partially inhibited the renin release elicited by 3 mg/kg (s.c.) of yohimbine. The prostaglandin synthetase inhibitors indomethacin (5 mg/kg s.c.) and meclofenamate (5 mg/kg s.c.) impaired the ability of yohimbine (3 mg/kg) to elevate SRA but did not alter the hemodynamic effects of yohimbine. Thus, the increase in renin release caused by yohimbine appears to be mediated by the sympathetic nervous system. Because the smaller doses of yohimbine increase renin release in the absence of a decrease in mean arterial pressure, it is unlikely that yohimbine stimulates renin release by baroreflex-mediated activation of the renal sympathetic nerves.(ABSTRACT TRUNCATED AT 250 WORDS)
Author List
Pfister SL, Keeton TKAuthor
Sandra L. Pfister PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsChlorisondamine
Hemodynamics
Indomethacin
Male
Meclofenamic Acid
Propranolol
Rats
Rats, Inbred Strains
Receptors, Adrenergic, alpha
Renin
Yohimbine